Corrosion resistant composition



Patented June 11, 1946 2,401,993 I CORROSION RESISTANT COIHPOSITIONJones I. Wasson, Union, and Gordon W. Duncan, Scotch Plains, N. J.,assignors to Standard Oil Development Company, a corporation of Dela- NoDrawing. Application December 31, 1942,

Serial No. 470,840

6 Claims. (01. 25mm 1 This invention relates to a new additive whichimparts corrosion resistant or rust preventing properties to organicmaterials, especially to mineral lubricating oils which are used incontact with iron or steel surfaces, particularly when substantialamounts of water are present.

The materials to which corrosion resistant or rust preventing propertiesare given by the additives of the present invention are particularly thelight mineral lubricating oils of about 50 to 1500 seconds viscositySaybolt at 100 F. which are suitable for use especially as turbineoils,' as hydraulic fluids or as lubricants for the bearings ofmachinery which is much in contact with water, such as paper mills, andas insulating oils in refrigerators, and in general in all cases where alubricating oil is used under conditions in which it may pick up orabsorb considerable amounts of water from atmospheric condensation orother sources of contamination. The additives may likewise be used inother lubricating oils and other petroleum fractions, such as fuels,where they are effective in preventing corrosion of tanks, lines, etc.from entrained moisture. In general,

they may be used to impart corrosion resistant properties to organicmaterials of a wide variety where water may become admixed therewith andtend to cause corrosion of metal surfaces; and by preventing suchcorrosion the additives also. greatly reduce wear between rubbingsurfaces of metals where they are present in lubricants.

It is generally known that many, if not most, of the additiveswhich areincorporated in mineral oil compositions to prevent rusting have adeleterious effect on the oxidation stability or life of the oil. Oilscontaining these compositions become peculiarly susceptible todeterioration by the action of oxygen. Also, many well knownantioxidants are effective in increasing the normal service life of theoil, but they do not impart corrosion resistant properties. It has nowbeen found, in accordance with the present inthe oxidation resistingefiect of antioxidants present, particularly when such antioxidant is atertiary butyl ether of a phenol.

It has been found that-the amine salt used 1 accordance with the presentinvention should preferably have at least 8 carbon atoms in the amineradical, but not more than about 14 carbon atoms. Salts derived fromhigher molecular Weight amines have been found not to be as effec- ,tivein reducing corrosion. Likewise, the amine radical is preferably astraight chain radical, rather than a branched or cyclic radical, sincethe latter have been found to be of little or no value in preventingrusting. The acid from which the salt is derived is an acid having acyclic nucleus with the carboxyl group attached thereto, and such cyclicnucleus may be a saturated nucleus, such as that found in naphthenicacids, or it may be an unsaturated nucleus, such as a benzene nucleus.The nucleus may have attached thereto additional atoms or groups, suchas halogen atoms, or alkyl, hydroxyl, nitro, mercapto,

, alkoxy, or similar groups. The amine or acid component of the salt maybe derived from pure compounds or from mixtures of compounds of similarnature. For example, the amines used in the preparation of the salts maybe pure amines, such as laurylamine, or they maybe technical mixtures,such as Lorol amine, which is a mixture of amines containing on theaverage from 10 to 14 carbon atoms per molecule and is derived from aproduct obtained in the catalytic hydrogenation of cocoanut oil acids.The latter composition has been found to be particularly effective inthe preparation of the corrosion resistant agents of the presentinvention. The

' acids found particularly useful are the naphthenic acids, benzoic acidand salicylic acid.

It has been mentioned above that the corrosion resistant additives ofthe present invention may be satisfactorily used in the presence ofantioxidants without preventing the latter from functioning effectively,as is often the case when corrosion preventing materials are added tolubricating oils and the like. The antioxidants which may be effectivelyused in the presence of the additives of the present invention are thealkyl ethersof phenols, phenols, amines, naphthols, and compounds oflike constitution.

In general, the quantity of the amine salt to be used will vary between0.01 and 0.5% by weight of the organic material to which it is added.The quantity to be used in a particular case will naturally" depend uponthe nature of the mateother soaps, other basic compounds, such as"heterocyclic bases or onium compounds, which may be used to absorbexcessive acid, also thickeners, oiliness agents and other ingredientsnormally employed as oil additives.

As indicated above, the new anticorrosion additive maybe used toadvantage with many types of organic substances in addition to thelubricating oils described above. erally in lubricating oils of alltypes, particularly those suitable for use in internal combustionengines, compressors, steam engines or Diesel en gines; also they may beused in industrial oils, e. g.. spindle oils and machinery lubricants,also in hydraulic and insulating oils. added to "white products obtainedfrom petroleum, such as kerosene, white oils, and waxes. They may alsobe used in'gasolines and other petroleum products of he motor fuel type.They may be used in dryin oils and in paints and other coatingcompositions and'in fatty oils of animal or vegetable origin. They areeffective in extreme pressure lubricants, etc., where they serve toprevent corrosion resulting from the liberation of hydrogen chloridefrom sulfurand chlorine-containing compounds present.

In the following example are shown the results of tests of a base oilalone and in combination with an antioxidant alone, and with anantioxidant in addition to various examples of the amine salts used inaccordance with the present invention. This example and the variouscompounds used therein to illustrate the present invention are not to beconsidered as limiting the scope of the invention in any way.

EXAMPLE The rate ofdeterioration of the oil was determined by theStaeger oxidation test which was conducted as follows:

200 cc. of the oiglmwer epoured into a glass beaker. To acceler aging, acleaned and polished copper strip 40 x 70 x 1 mm. was 'put into thebeaker as a catalyst. The beaker containin the oil and catalyst wasplaced on a rotating shelf in an oven, the oven temperature beingmaintained at 110 C. and the shelf rotated at 5-6 R. P. M. Purified airwas blown through the oven at the rate of 1.5 to 2 cu. ft. per hour The.life of the oil was determined by observing the time required for theoil to show deterioration as evidenced by a neutralization number of0.2.

They may be used gen- They may be Table I Oforggslioxn Hoursflliie o s eo Oil composition oi1+m% (stagger 5 water test) (A) 39.59 oil Heavy 72(B) Base oil+0.l% tert. buytl ether of do- 410 ortho tert. butylpara-cresol. (0) Base oil+0.25% tert. butyl ether of do 790 ortho tert.butyl para-cresol.

(D) Oil B+t0.02% lorol" amine naph- Nil 312 one e. E) Oil B+0.027 loroamine benzoate- F) Oil 0 0.0 lorol" amine benzoate. 490 G) Oil B 0.0 a"lor0l amine salicylate. do 235 (H) Oil B+0.02% lorol amine isooctyl do305 salicylate. (1) Oil B+0.05% lei-o1" amine stearate Light"--- 365 (J)Oil B+0.05% lorol amine oleate do-- 365 (K) Oil bBe+0.05% octadecylaminebenz- Medium- 315 0a (L) Oil C+0.02% dicyclohexylamine Heavy. 455

-- naphthenate.

1 Prepared by reacting "lorol amine with an alkylated salicylic acidprepared by the Kolbe synthesis, in which 68' parts of the sodium saltoi lsocctyl henol and 200 parts oi pyridine were heated further treatedwith sodium carbonate to se The results of the tests are recorded in thefollowing table:

to -240 O. for 8-5 ours in a bomb in the presence oi carbon dioxide. Theproduct was acidified and washed with water and crate it from thephenol.

The salt formed was separated, acidiile and extracted with a solvent.

It can be seen from the above data that the amine salts prepared fromstraight chain aliphatic acids, or from amines having an excessivelylong chain, or from cycloalkyl amines, are not as satisfactory ascorrosion preventing agents as those prepared in accordance with thepresent invention. When the preferred amine salts are used, thecorrosion is entirely eliminated and the Staeger life test shows thehigh resistance to oxidation.

This invention is not to be considered as limited by any of the examplesmentioned or described herein, but solely by the terms of the appendedclaims.

We claim:

1. A method of lubricating steel bearings under corrosion inhibitedconditions in the presence of substantial amounts of Water, whichcomprises employing in the lubrication of said bearings a minerallubricating oil containing a tertiary butylether of ortho tertiary butylparacresol and about 0.01 to about 0.5% of lorol amine salicylate in anamount sufilcient to exert a corrosion inhibitory effect.

2. The method of lubricating ferrous metal surfaces under corrosioninhibited conditions in the presence of substantial amounts of Waternormally sufiicient to cause corrosion, which comprises employing in thelubrication of said surfaces a mineral lubricating oil containing lorol"amine salicylate in amount sufficient to inhibit corrosion.

3. The method of lubricating ferrous metal surfaces under corrosioninhibited conditions in the presence of substantial amounts of waternormally sufficient to cause corrosion, which comprises employing in thelubrication of said surfaces a mineral lubricating oil containing a saltof lorol amine and an organic acid of the class consisting of salicylicacid, napthenic acid and benzoic acid in amount sufficient to inhibitcorrosion.

4. The method according to claim 3 in which the acid is salicylic acid.

5. The method according to claim 3 in which the acid is naphthenic acid.

6. The method according to claim 3 in which the acid is benzoic acid.

JONES- I. WASSON. GORDON W. DUNCAN.

